The invention concerns a mechanical seal comprising a counter ring and a slide ring arranged in a housing in which a collecting space for a coolant/lubricant is provided into which at least one inlet conduit line opens.
Mechanical seals are used, for example, in water pumps of automobiles. The mechanical seal must be embodied in such a way that it can be operated without the liquid to be sealed for a sufficiently long period. The heat generated in the sealing gap between counter ring and slide ring should not cause thermal damage of the sliding partners themselves nor should it cause thermal damage of the sealing components surrounding the sliding partners. So that in dry run conditions a sufficiently low sealing gap temperature is reached, special coal graphite materials which are relatively soft are used for the slide ring. However, such materials are not very resistant toward abrasive attack. The counter ring is typically made of a hard material, like SiC. Such a soft/hard sliding pair has therefore a lower life span than a hard/hard sliding pair in which the counter ring and the slide ring are made, for example, from SiC. Such sliding pairs however have relatively bad dry run properties. The mechanical seal is provided therefore with a collecting space in which coolant/lubricant is stored that imparts to the mechanical seal the required dry run permanence, even when a soft/hard sliding pair is used. The inlet conduit serves to transport coolant/lubricant from the receiving space of the pump to the collecting space of the mechanical seal.
The object of the invention is to embody a mechanical seal of the aforementioned kind in such a way that the inlet conduit can be provided in an easy manner in the mechanical seal. In this connection, the inlet conduit should be provided in such a way that the coolant/lubricant contained in the collecting space resides for a longer period of time in the collecting space when the mechanical seal works in dry run conditions.